Synergistic Field Crop Pest Management Properties of Plant-Derived Essential Oils in Combination with Synthetic Pesticides and Bioactive Molecules: A Review

Abstract

The management of insect pests and fungal diseases that cause damage to crops has become challenging due to the rise of pesticide and fungicide resistance. The recent developments in studies related to plant-derived essential oil products has led to the discovery of a range of phytochemicals with the potential to combat pesticide and fungicide resistance. This review paper summarizes and interprets the findings of experimental work based on plant-based essential oils in combination with existing pesticidal and fungicidal agents and novel bioactive natural and synthetic molecules against the insect pests and fungi responsible for the damage of crops. The insect mortality rate and fractional inhibitory concentration were used to evaluate the insecticidal and fungicidal activities of essential oil synergists against crop-associated pests. A number of studies have revealed that plant-derived essential oils are capable of enhancing the insect mortality rate and reducing the minimum inhibitory concentration of commercially available pesticides, fungicides and other bioactive molecules. Considering these facts, plant-derived essential oils represent a valuable and novel source of bioactive compounds with potent synergism to modulate crop-associated insect pests and phytopathogenic fungi.

The Antifungal Activity of Cinnamon-Litsea Combined Essential Oil against Dominant Fungal Strains of Moldy Peanut Kernels

“…EO was 6.25 µg/mL, lower than that of fluconazole (256 µg/mL). Studies have also shown that EO can act as enhancers of commercial antifungal agents to enhance the antifungal activity, and EOs are potential alternatives to synthetic fungicides [ 41 , 42 , 43 ]. In addition, the optimal volume ratio of CLCEO with strongest antifungal effect against A .…”

Methyl Benzoate as a Promising, Environmentally Safe Insecticide: Current Status and Future Perspectives

“…The method of action of plant-derived EOs has been determined in a few cases at the molecular level. Studies have found that EO compounds change the activities of various bioactive target molecules within the cells, including acetylcholinesterase (AChE), octopamine, and gamma-aminobutyric acid (GABA), in insects [123][124][125]. The AChE of insects is an important potential target molecule of various plant-derived EOs [123].…”

The synergistic effects of rosehip oil and matrine against Icerya aegyptiaca (Douglas) (Hemiptera: Coccoidea) and the underlying mechanisms

“…PEOs can be used as an insecticide synergist and effectively enhance the control effect of insecticides. The addition of PEOs makes synthetic insecticides more resistant to rain erosion after spraying, drought and evaporation, and insecticide spread and penetration are enhanced, with obvious synergistic and decrement effects 13–15 . Essential oils or their components can also inhibit certain detoxification enzymes in insects, alleviate the rate at which insecticides are degraded and thereby enhance insecticidal effects 16,17 …”

“…The addition of PEOs makes synthetic insecticides more resistant to rain erosion after spraying, drought and evaporation, and insecticide spread and penetration are enhanced, with obvious synergistic and decrement effects. [13][14][15] Essential oils or their components can also inhibit certain detoxification enzymes in insects, alleviate the rate at which insecticides are degraded and thereby enhance insecticidal effects. 16,17 Botanicals show low toxicity toward non-target organisms, decompose easily in the environment without the risks posed by insecticide residues, and potentially have broad application in agriculture.…”